If you look up when lounging on the beach at Redfish Lake or the shores of the Salmon River, chances are you will see a large bird flying over. Chances are that will most likely be an Osprey (Pandion haliaetus)!Ospreys are also known as sea hawks, river hawks, and fish hawks. They are part of the raptor family and can reach more than 2 feet in length and roughly have a 6-foot wingspan. Ospreys are dark brown plumage on their backs. Depending on the angle you can mistake them for bald eagles but their grey/white head and underbelly are distinctly different than the eagle’s.
These birds of prey have caught human’s attention for the past 2,500 years. In the 19th and early 20th century people would collect osprey’s eggs and hunt down adults. The main threat to the osprey population was in the 1950’s and 1960’s with the use of DDT and other insecticides. These pollutants would runoff from farmlands into waterways and trickle down throughout the food web. The pesticide would result in thin-shelled eggs that were easily broken and/or resulted in infertile eggs. When DDT was banned in the 1970’s osprey populations began to slowly increase and today they are no longer in threat of being endangered.
Ospreys are master anglers, and it is a good thing because their diet is thought to be 99% fish. They usually have about a 70 percent success rate when they are fishing. They dive from 30 to 100 feet above the water, tucking their feet and head together, at a speed up to 30 miles per hour, to catch their prey. They are unlike other raptors because of their reversible outer toe that helps them grasp their catch with two toes on either side of the body. This adaptation allows them rotate fish parallel to their body during flight, making travel more aerodynamic with prey in their talons. They often fully submerge themselves in water when catching a fish, which most other raptors cannot do. If you are out fishing and not having any luck, look around, you might get lucky to see an osprey catch the fish you have been waiting for.
Ospreys are migratory birds. Scientists have been using small tracking devices they attach to the birds to watch their migratory patterns. They breed in the north and migrate south for winter. In their lifetime, which is usually a span of 15 to 20 years, they can travel 160,000 migration miles. Locals often look to ospreys as a sign of spring here in the Sawtooth Mountains!
Next time you are sitting on the shore of Redfish Lake, look up! You might be able to see our resident osprey. Or, if you are enjoying the river you might be able to see an osprey dive down to catch their lunch.
Written by Naturalist Laura Fitzgerald